Photocatalytic synthesis of 2,3-diamines from anilines and DIPEA via C–N bond cleavage and C–C bond formation.

2,3-Diamines are skeleton structures widely found in natural products and drug molecules and can also be used as ligands in transition metal catalysis. A novel visible light-driven synthesis method for 2,3-diamines using anilines and diisopropylethylamine as starting materials and aldehydes as proton acceptors under the action of the organic photosensitiser 4CzIPN has been developed. The method has mild conditions, avoids the use of metal reagents and the reaction mechanism does not involve the imine intermediate. Under optimal conditions, the yield of 2,3-diamines is up to 90%. In addition, the aldehydes give rise to 2,3-diols after the reaction, which means that the method can synthesise diamines and diols in one pot. [ABSTRACT FROM AUTHOR]